Problem with raid10 array

vredg0

Commendable
Mar 19, 2016
3
0
1,510
Hi

I'm having problem with my Linux raid10 4 disk array (it is changing size to 0 bytes and thus stopping).
"md0: detected capacity change from 8001301774336 to 0
md: md0 stopped."

As I can't use the sata power connections on my newly bought power supply as it's too short between the connections on the cables I'm using molex to 2 sata power converters.

One molex cable with three connections therefore are powering four 5400 rpm disks and a ssd used for the root filesystem. Do you think this could be the root of the problem.

Or is faulty disks (they are new and short smart test shows OK) a more probable cause of the problem? I'm also reusing one of my old sata data cables (all other are new)
 

marko55

Honorable
Nov 29, 2015
800
0
11,660
If you can, test the HDDs in another computer, or oven using a SATA-to-USB converter and connect to a laptop. That'll answer that question.

Power is extremely important with hard drives, especially with RAID. Most mobile racks (4 x HDDs in 3 x 5.25 bays for instance) distribute power to their drives using less power connections than drives so this is normal. I only ever use 1-to-1 power connections though, even though that single power cable coming out of your PSU can power probably 8 drives or more. Your problem could simply be that you're using a molex to SATA power converter AND you're going from 1 to 2. I'd grab some 1-to-1 SATA power extension cables and use those to verify. I use these in every single build i do. You could also use a 1-to-2 SATA power connector.

Note that you could even have a PSU issue. I just had to RMA one because the workstation would just cut off during boot when the 5 x 2TB HDDs would start to spin up. Felt like an under voltage issue. Replacing the PSU cleared it right up. Depending on the quality of your PSU you just may not be able to do any splitters.
 

vredg0

Commendable
Mar 19, 2016
3
0
1,510
Thanks for the answers! I'm using more power cables to the disks now (only using one of the two sata connections from the splitter and also changed some sata data cables and have re-created the raid. Using it now and monitoring for problems.

I'm using WD Red WD40EFRX 4tb (the standard ones) disks.
 

vredg0

Commendable
Mar 19, 2016
3
0
1,510
I'm an idiot. I did a write benchmark with dd to the array and destroyed it myself. Did not think of that at once.
Sorry guys for having wasted your time.